Security device

ABSTRACT

A pair of jaws are mounted in a housing for engagement around the kingpin of a trailer. The jaws when closed may be locked to prevent the removal of the device from the kingpin. The bottom wall of the housing is provided with a guide way to guide the kingpin into engagement with the jaws and the jaws will rest on the head of the kingpin when closed. The housing side walls are deformable to permanently lock the jaws closed if struck by an external force.

United States Patent Owen 51 Dec. 19, 1972 [5 SECURITY DEVICE 2,440,744 5/1948 Grinnel et al ..70/232 [72] Inventor: Alvin L. Owen 3244 West Lake 3,386,274 6/l968 Mclntyre ..70/232 N. dfiggg izg g Parkway E Re Primary Examiner-Albert G. Craig, Jr.

AttorneySeed, Berry & Dowrey [73] Assignee: Alvin L. Owen, Redmond, Wash. [22 Filed: March 4, 1971 [57] ABSTRACT [21] APPL No: 121,073 A pair of jaws are mounted in a housing for engagement around the kingpin of a trailer. The Jaws when closed may be locked to prevent the removal of the U-S- Cl- E device from the kingpin The bottom wall of the bong. [51] Int. Cl. ..B60r 25/00, Fl6b 41/00 ing is Provided with a guide way to id the kingpin [58] new of Search "70/14, 258; into engagement with the jaws and the jaws will rest 232/41 E; 248/203 on the head of the kingpin when closed. The housing side walls are deformable to permanently lock the [546] Reeremes Cted jaws closed if struck by an external force.

UNITED STATES PATENTS 4 Claims, 4'Drawing Figures 1,222,086 4/1917 Erickson ..232/4l E 934,481 9/1909 Trevor 7v PATENTED 19 I97? 3 706, 21 1 FIG 11 FIG. 2

INVENTOR. ALVIN L. OWEN ATTORNEYS SECURITY DEVICE BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to theft prevention devices for conventional trailers of the type having a downwardly depending kingpin on the trailer.

2. Description of the Prior Art Various types of security devices to prevent the unauthorized attachment of a tractor to a trailer have been heretofore known. These security devices in order to be effective must be made of extremely heavy duty materials. As a result they are generally quite heavy and thus difficult to place into a locking position around the kingpin.

Typical of these prior art devices is the locking means illustrated in the United States patent to McIntyre, U.S. Pat. No. 3,112,636. In this patent a pair of pivotal jaws are mounted in a housing which is inserted over the kingpin of a trailer in a direction coaxial with the axis of the kingpin. The person installing this device must lift the housing vertically upward centering it over the kingpin and then must hold it while closing the jaws over the shank of the kingpin. Such an installation is difficult since the housing must be held by one hand while the jaws are closed with the other.

It is frequently the practice in the unauthorized removal of these security devices to ram the device with the coupler of the tractor or to bludgeon the device with a heavy object. In prior art devices the forces of these blows would be sufficient to brake the jaws thus freeing the device from the kingpin.

SUMMARY OF THE INVENTION It is an object of this invention to provide a security device which is constructed of heavy-duty materials but which is easily placed into locking engagement with the kingpin of a trailer.

It is another object of the invention to provide a security device having pivotal jaws which engage the kingpin of a trailer and a housing which will deform to positively lock the jaws when struck or bludgeoned inwardly.

Basically the security device includes a pair of jaws which are moveable into encircling engagement around the shank of the kingpin and which may be locked against unauthorized opening. The jaws are surrounded by a housing which has an opening for allowing the device to be slid perpendicular to the axis of the kingpin into engagement with the kingpin with the jaws being automatically closed and supporting the weight of the device on the head of the kingpin. In the preferred form of the invention the housing has sidewalls that are readily deformable into locking engagement with the jaws if bludgeoned or struck by another external force.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective of the security device embodying the principle of the invention.

FIG. 2 is a transverse section taken along the line 2 2 of FIG. 3.

FIG. 3 is a horizontal section of the security device.

FIG. 4 is an isometric illustration showing the jaws closed.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As best shown in FIGS. 1 and 2 the security device includes ahousing 10 having a bottom wall 12, vertical sidewalls 14 and 16, and a top wall 18. The top wall 18 is provided with a central slot 20 terminating at its outer end at recesses 22 in the sidewalls. The bottom wall 12 is provided with an internal guide way 24.

As is best shown in FIG. 2 a pair of jaws 30 and 32 are pivotally mounted within the housing 10. The jaws are provided with shank receiving recesses 34 and locking recesses 36. As best shown in FIG. 2 the lower surfaces of the jaws are spaced above the bottom wall 12 so that the head of the kingpin P may be nested between the jaws and the bottom wall in the guide way 24. The jaws'are provided with rearward ends or abutment surfaces 38 which are engaged by the kingpin and will rotate the jaws into the close position shown in solid lines in FIG. 4. I 4

Locking means is provided for holding the jaws in the closed position. The locking means is best shown in. FIGS. 3 and 4 and includes a conventional combination lock 40 having a block 42 which is insertable and may be locked between the locking recesses 36 of the jaws.

In operation the device is unlocked and the jaws spread into the position shown in FIG. 3. The housing is then slid over the head of a kingpin 'P with the head guided between the jaws by the guide way 24. As the housing is moved over the kingpin the shank of the kingpin will push against the abutment surfaces 38 swinging the jaws closed around the shank of the kingpin. At this point the housing, which may weigh 20 to 30 lbs, is supported solely on the lower surfaces of the kingpin and the operator may remove his hands from the housing. The operator is then free to reach beneath the housing and rotate the tumblers of the combination lock.

As is readily apparent the heaviest structural portion of the housing 10 is the tapered end around the locking mechanism 40. It is contemplated that personnel installing the security device will normally position this tapered end portion of the housing toward the front of the trailer so that if the tractor operator accidentally backs his vehicle against the security device the device will withstand the force of the impact and may still be removed. The wider end adjacent the recesses 22, however, is more readily deformable. It is contemplated that in the theft of a trailer the thief will attempt to remove the security device by attacking it at this point because of its lesser structural strength probably by backing the vehicle into it or striking it with a heavy object. By making this portion of the housing more deformable, however, the internally directed force will bend or crumple the housing toward the jaws 34 precluding the removal of them. In fact, the security device will probably be removable only by cutting it from the kingpin as with a torch or alike.

While the preferred form of the invention has been illustrated and described it should be understood that it may be modified without departing from the principles of the invention. It is therefore intended that the scope of the invention shall be limited only by the claims appended hereto.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

l. A security device for locking a trailer kingpin of the type having a shank and an enlarged head against unauthorized use comprising a pair of jaws movable between open and closed positions, said jaws having shank receiving portions for engaging the kingpin shank, abutment surfaces operable to engage the shank for closing the jaws around the shank upon movement of the jaws against the shank, and lower surfaces for resting on the head of the kingpin when the jaws are closed whereby the weight of the device is supported by the kingpin, a housing surrounding the jaws, said housing including top and bottom walls, said housing supporting locking means engageable with the jaws for precluding movement thereon into the open position, and guide means in said housing for guiding the jaws into engagement with the kingpin in a direction perpendicular to the shank axis, said guide means including a slot in said top wall aligned with said shank receiving portions of said jaws, and an internal guideway on said bottom wall for receiving the head of the kingpin.

2. The device of claim 1 said housing including deformable sidewalls adjacent the jaws for preventing their opening when the sidewalls are inwardly deformed.

3. The device of claim 1 said jaws including rearward locking recesses, said locking means including a block positionable within said recesses, each jaw being pivotally mounted within the housing with the shank receiving recess on the opposite side of the pivot from the locking recess whereby pivoting the pins into the open position is precluded when said block is within the locking recesses.

4. The device of claim 3 said housing including deformable side walls adjacent the jaws for preventing their opening when the sidewalls are inwardly deformed.

* 8K IF l 

1. A security device for locking a trailer kingpin of the type having a shank and an enlarged head against unauthorized use comprising a pair of jaws movable between open and closed positions, said jaws having shank receiving portions for engaging the kingpin shank, abutment surfaces operable to engage the shank for closing the jaws around the shank upon movement of the jaws against the shank, and lower surfaces for resting on the head of the kingpin when the jaws are closed whereby the weight of the device is supported by the kingpin, a housing surrounding the jaws, said housing including top and bottom walls, said housing supporting locking means engageable with the jaws for precluding movement theReon into the open position, and guide means in said housing for guiding the jaws into engagement with the kingpin in a direction perpendicular to the shank axis, said guide means including a slot in said top wall aligned with said shank receiving portions of said jaws, and an internal guideway on said bottom wall for receiving the head of the kingpin.
 2. The device of claim 1 said housing including deformable sidewalls adjacent the jaws for preventing their opening when the sidewalls are inwardly deformed.
 3. The device of claim 1 said jaws including rearward locking recesses, said locking means including a block positionable within said recesses, each jaw being pivotally mounted within the housing with the shank receiving recess on the opposite side of the pivot from the locking recess whereby pivoting the pins into the open position is precluded when said block is within the locking recesses.
 4. The device of claim 3 said housing including deformable side walls adjacent the jaws for preventing their opening when the sidewalls are inwardly deformed. 